Article Mapping Coastal Wetlands of the Bohai Rim at a Spatial Resolution of 10 m Using Multiple Open- Access Satellite Data and Terrain Indices

Shaobo Sun 1,2, Yonggen Zhang 1,2, Zhaoliang Song 1,2,*, Baozhang Chen 3, Yangjian Zhang 4, Wenping Yuan 5, Chu Chen 6, Wei Chen 1,2, Xiangbin Ran 7 and Yidong Wang 8

1 Institute of Surface-Earth System Science, School of Earth System Science, University, Tianjin 300072, ; [email protected] (S.S.); [email protected] (Y.Z; [email protected] (W.C.) 2 Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China 3 State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, 100101, China; [email protected] (B.C.) 4 Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; [email protected] (Y.Z.) 5 School of Atmospheric Sciences, Province Key Laboratory for Climate Change and Natural Disaster Studies, Zhuhai Key Laboratory of Dynamics Urban Climate and Ecology, Sun Yat- sen University, Zhuhai, Guangdong 510245, China; [email protected] (W.Y.) 6 Tianjin Institute of Surveying and Mapping Co., Ltd., Tianjin 300381, China; [email protected] (C.C.) 7 Research Center for Marine Ecology, First Institute of Oceanography, Ministry Natural Resources, Qingdao 266061, China; [email protected] (X.R.) 8 Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China; [email protected] (Y.W.) * Correspondence: .); [email protected] (Z.S.) Tel.: +86-022-2740-5053

Remote Sens. 2020, 12, 4114; doi:10.3390/rs12244114 www.mdpi.com/journal/remotesensing Remote Sens. 2020, 12, 4114 2 of 4

Figure 1. Spatial distributions of the training samples and validation samples.

Remote Sens. 2020, 12, 4114; doi:10.3390/rs12244114 www.mdpi.com/journal/remotesensing Remote Sens. 2020, 12, 4114 3 of 4

Figure 2. Location and satellite remote sensing image of the Beidagang wetland. The satellite image is from the ArcGIS World imagery

(https://www.arcgis.com/home/webmap/viewer.html?useExisting=1&layers=10df2279f9684e4 a9f6a7f08febac2a9).

Table S1 Statistics of the area of Bohai rim coastal wetlands based different data.

Percent of wetland Data Costal wetland area (km2) Data time pixels BRCW10 8095.8462 8.08% 2018-2019

GlobLand30 8660.3878 8.96% 2010

FROM-GLC10 6560.6170 6.52% 2017

Remote Sens. 2020, 12, 4114; doi:10.3390/rs12244114 www.mdpi.com/journal/remotesensing Remote Sens. 2020, 12, 4114 4 of 4

Remote Sens. 2020, 12, 4114; doi:10.3390/rs12244114 www.mdpi.com/journal/remotesensing